Fetch libmonet in build.sh and document monet colours

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

README.md

@@ -47,7 +47,7 @@ sudo dnf install fcitx5-devel extra-cmake-modules cairo-devel pango-devel \
 然后:
 
 ```
-scripts/build.sh      # 下载 Fcitx5 和 yoga 源码,叠加 src/,构建 m3ui
+scripts/build.sh      # 下载 Fcitx5、yoga 和 libmonet 源码,叠加 src/,构建 m3ui
 scripts/install.sh    # 安装到 ~/.local,不改动 $HOME 以外的任何东西
 ```
 
@@ -56,6 +56,12 @@ scripts/install.sh    # 安装到 ~/.local,不改动 $HOME 以外的任何东西
 没有固定提交的版本会被拒绝,除非你自己用 `FCITX_COMMIT=<sha>` 指定。这个插件跑在输入法进程里,
 看得到你打的所有字,所以构建来源值得认真对待。
 
+## 莫奈取色
+
+候选窗的颜色由 [libmonet](https://git.oeo.one/justme/libmonet) 从桌面强调色生成(`UseMonet=True`,默认开),
+深浅色跟随系统。输入法进程内不会启动任何子进程:直接复用 Fcitx5 自己监听的 XDG portal
+(KDE Plasma 6、GNOME 47+ 都有),取不到时回退到默认的粉色。`UseMonet=False` 回到主题文件里的固定颜色。
+
 ## 使用
 
 手动试用:

config/m3ui.conf.example

@@ -10,6 +10,7 @@ UseAccentColor=False
 PerScreenDPI=True
 ForceWaylandDPI=0
 EnableFractionalScale=True
+UseMonet=True
 Animations=True
 Bounce=True
 SpatialStiffness=2000

scripts/build.sh

@@ -27,6 +27,8 @@ commit=${FCITX_COMMIT:-${known_commits[$version]:-}}
 [ -n "$commit" ] || die "no pinned commit for Fcitx5 $version. Look up the commit of its tag and pass it as FCITX_COMMIT=<sha>"
 # Commit of the yoga submodule pinned by Fcitx5 (third_party/yoga).
 yoga_commit=${YOGA_COMMIT:-042f5013152eb81c1552dec945b88f7b95ca350f}
+# libmonet (header-only) supplies the colours derived from the desktop accent.
+monet_commit=${MONET_COMMIT:-b97a55ac75ae82435628dc585cccadb45e4d2feb}
 
 # fetch_commit <url> <dir> <commit>, leaves <dir> checked out at exactly <commit>
 fetch_commit() {
@@ -48,6 +50,8 @@ echo ">> fetching Fcitx5 $version ($commit)"
 fetch_commit https://github.com/fcitx/fcitx5 "$srcdir" "$commit"
 echo ">> fetching yoga ($yoga_commit)"
 fetch_commit https://github.com/facebook/yoga "$srcdir/third_party/yoga" "$yoga_commit"
+echo ">> fetching libmonet ($monet_commit)"
+fetch_commit https://git.oeo.one/justme/libmonet.git "$work/libmonet" "$monet_commit"
 [ -z "${FETCH_ONLY:-}" ] || { echo ">> sources are in place"; exit 0; }
 
 echo ">> overlaying m3ui"
@@ -61,6 +65,7 @@ fi
 echo ">> configuring"
 cmake -S "$srcdir" -B "$work/cmake" -G Ninja \
     -DCMAKE_BUILD_TYPE=Release \
+    -DMONET_INCLUDE_DIR="$work/libmonet/include" \
     -DCMAKE_INSTALL_PREFIX="${PREFIX:-$HOME/.local/m3ui}" \
     -DENABLE_X11=On -DENABLE_WAYLAND=On \
     -DENABLE_TEST=Off -DENABLE_TESTING_ADDONS=Off -DENABLE_ENCHANT=Off \

src/CMakeLists.txt

@@ -29,6 +29,12 @@ if (ENABLE_DBUS)
     set(CLASSICUI_LIBS ${CLASSICUI_LIBS} Fcitx5::Module::DBus)
 endif()
 
+# libmonet, the shared colour code, header only. build.sh fetches it at a pinned
+# commit and passes the directory.
+if (NOT MONET_INCLUDE_DIR OR NOT EXISTS "${MONET_INCLUDE_DIR}/monet/monet.h")
+    message(FATAL_ERROR "MONET_INCLUDE_DIR must point at the include directory of libmonet")
+endif()
+
 add_fcitx5_addon(m3ui
     classicui.cpp window.cpp theme.cpp inputwindow.cpp plasmathemewatchdog.cpp colorhelper.cpp ${CLASSICUI_SRCS}
     )
@@ -37,6 +43,8 @@ if (ENABLE_X11)
 target_compile_definitions(m3ui PRIVATE -DFCITX_XCB_EWMH)
 endif()
 
+target_include_directories(m3ui PRIVATE "${MONET_INCLUDE_DIR}")
+
 target_link_libraries(m3ui
     Fcitx5::Core
     PkgConfig::Cairo PkgConfig::Pango

src/classicui.cpp

@@ -7,6 +7,7 @@
 
 #include "classicui.h"
 #include <fcntl.h>
+#include <cmath>
 #include <cstddef>
 #include <cstdint>
 #include <filesystem>
@@ -180,6 +181,7 @@ void M3UI::reloadTheme() {
             auto color = variant.dataAs<uint32_t>();
             auto oldIsDark = isDark_;
             isDark_ = (color == 1);
+            portalSchemeKnown_ = true;
             if (oldIsDark != isDark_) {
                 CLASSICUI_DEBUG() << "XDG Portal AppearanceChanged "
                                      "isDark"
@@ -189,8 +191,10 @@ void M3UI::reloadTheme() {
         }
     };
 
+    // The portal is also how the colours for UseMonet are learned, over the
+    // connection Fcitx5 already has, so nothing has to be started for it.
     if (dbus()) {
-        if (*config_.useDarkTheme) {
+        if (*config_.useDarkTheme || *config_.useMonet) {
             if (!darkModeEntry_ && settingMonitor_) {
                 darkModeEntry_ = settingMonitor_->watch(
                     "org.freedesktop.appearance", "color-scheme", parseMessage);
@@ -253,7 +257,7 @@ void M3UI::reloadTheme() {
     };
 
     if (dbus()) {
-        if (*config_.useAccentColor) {
+        if (*config_.useAccentColor || *config_.useMonet) {
             if (!accentColorEntry_ && settingMonitor_) {
                 accentColorEntry_ =
                     settingMonitor_->watch("org.freedesktop.appearance",
@@ -266,7 +270,53 @@ void M3UI::reloadTheme() {
     }
 #endif
 
-    theme_.populateColor(accentColor_);
+    if (*config_.useMonet) {
+        theme_.applyMonet(mapScheme(monetScheme()));
+    }
+    // The accent colour is only watched for UseMonet, it must not recolour the
+    // fields of a classic theme unless the user asked for that.
+    theme_.populateColor(*config_.useAccentColor ? accentColor_
+                                                  : std::nullopt);
+}
+
+monet::Scheme M3UI::monetScheme() const {
+    // Nothing is ever started from here: a slow program would stall the input
+    // method. The portal is read through the connection Fcitx5 has, the other
+    // sources only read files.
+    monet::Context ctx = monet::Context::system();
+    ctx.run = [](const std::vector<std::string> &, int) {
+        return std::optional<std::string>();
+    };
+    monet::Source portal{
+        "fcitx-portal", [this](const monet::Context &) {
+            monet::Appearance a;
+            if (accentColor_) {
+                auto q = [](float c) {
+                    return static_cast<std::uint8_t>(std::lround(c * 255.0f));
+                };
+                a.accent = monet::Rgb{q(accentColor_->redF()),
+                                      q(accentColor_->greenF()),
+                                      q(accentColor_->blueF())};
+            }
+            if (portalSchemeKnown_) {
+                a.mode = isDark_ ? monet::Mode::Dark : monet::Mode::Light;
+            }
+            return a;
+        }};
+    // MONET_SEED and MONET_MODE first, then what the portal said, then the rest.
+    std::vector<monet::Source> sources;
+    for (auto &source : monet::defaultSources(ctx)) {
+        sources.push_back(std::move(source));
+        if (sources.back().name == "override") {
+            sources.push_back(portal);
+        }
+    }
+    const monet::Appearance a = monet::detect(ctx, sources);
+    CLASSICUI_DEBUG() << "Monet seed " << monet::hex(*a.accent) << " from "
+                      << a.accentSource << ", "
+                      << (*a.mode == monet::Mode::Dark ? "dark" : "light")
+                      << " from " << a.modeSource;
+    return monet::generate(*a.accent, *a.mode);
 }
 
 void M3UI::suspend() {

src/classicui.h

@@ -201,6 +201,11 @@ FCITX_CONFIGURATION(
                "font DPI. If the value is 0, it means this option is "
                "disabled.")}};
 
+    Option<bool> useMonet{
+        this, "UseMonet",
+        _("Take the colours from the desktop: its accent colour and its light "
+          "or dark setting"),
+        true};
     Option<bool> animations{this, "Animations", _("Enable animations"), true};
     Option<bool> bounce{this, "Bounce",
                         _("Bouncy overshoot (off: critically damped)"), true};
@@ -244,6 +249,8 @@ public:
     FCITX_ADDON_DEPENDENCY_LOADER(dbus, instance_->addonManager());
     Instance *instance() const { return instance_; }
     const Configuration *getConfig() const override;
+    // The scheme for the current desktop colours, see classicui.cpp.
+    monet::Scheme monetScheme() const;
     void setConfig(const RawConfig &config) override {
         config_.load(config, true);
         safeSaveAsIni(config_, "conf/m3ui.conf");
@@ -330,6 +337,8 @@ private:
     mutable Theme subconfigTheme_;
     bool suspended_ = true;
     bool isDark_ = false;
+    // The portal has answered, so isDark_ is a value and not just the default.
+    bool portalSchemeKnown_ = false;
     std::optional<Color> accentColor_ = std::nullopt;
 
     std::unique_ptr<EventSource> deferedEnableTray_;

src/monettheme.h

@@ -0,0 +1,46 @@
+#pragma once
+
+#include <monet/monet.h>
+
+#include "fcitx-utils/color.h"
+
+namespace fcitx::m3ui {
+
+// The colours of the candidate window that follow the desktop, taken from a
+// libmonet scheme. Only colours are decided here, the radii and the spacing stay
+// with the theme file.
+struct MonetColors {
+    Color surface;               // the panel
+    Color outline;               // its border
+    Color highlightFill;         // the pill behind the current candidate
+    Color normal;                // candidate text and the typed pinyin
+    Color highlight;             // the part of the typed pinyin being converted
+    Color highlightBackground;
+    Color highlightCandidate;    // text on the pill
+    Color candidateLabel;        // the number in front of a candidate
+    Color highlightCandidateLabel;
+    Color candidateComment;
+    Color highlightCandidateComment;
+};
+
+inline Color toColor(monet::Rgb c, int alpha = 255) {
+    return Color(c.r, c.g, c.b, static_cast<unsigned short>(alpha));
+}
+
+inline MonetColors mapScheme(const monet::Scheme &s) {
+    MonetColors c;
+    c.surface = toColor(s.surfaceContainer, 245);
+    c.outline = toColor(s.outlineVariant);
+    c.highlightFill = toColor(s.primaryContainer);
+    c.normal = toColor(s.onSurface);
+    c.highlight = toColor(s.primary);
+    c.highlightBackground = toColor(s.primaryContainer);
+    c.highlightCandidate = toColor(s.onPrimaryContainer);
+    c.candidateLabel = toColor(s.onSurfaceVariant);
+    c.highlightCandidateLabel = toColor(s.onPrimaryContainer);
+    c.candidateComment = toColor(s.onSurfaceVariant);
+    c.highlightCandidateComment = toColor(s.onPrimaryContainer);
+    return c;
+}
+
+} // namespace fcitx::m3ui

src/theme.cpp

@@ -1180,6 +1180,25 @@ std::vector<Rect> Theme::mask(const BackgroundImageConfig &cfg, int width,
     return result;
 }
 
+void Theme::applyMonet(const MonetColors &c) {
+    // A classic theme draws its panel from images, there is nothing to recolour.
+    if (inputPanel->surfaceColor->alpha() == 0) {
+        return;
+    }
+    auto *panel = inputPanel.mutableValue();
+    panel->surfaceColor.setValue(c.surface);
+    panel->outlineColor.setValue(c.outline);
+    panel->highlightFillColor.setValue(c.highlightFill);
+    panel->normalColor.setValue(c.normal);
+    panel->highlightColor.setValue(c.highlight);
+    panel->highlightBackgroundColor.setValue(c.highlightBackground);
+    panel->highlightCandidateColor.setValue(c.highlightCandidate);
+    panel->candidateLabelColor.setValue(c.candidateLabel);
+    panel->highlightCandidateLabelColor.setValue(c.highlightCandidateLabel);
+    panel->candidateCommentColor.setValue(c.candidateComment);
+    panel->highlightCandidateCommentColor.setValue(c.highlightCandidateComment);
+}
+
 void Theme::populateColor(std::optional<Color> accent) {
     inputPanelBackground_ = *inputPanel->background->color;
     inputPanelBorder_ = *inputPanel->background->borderColor;

src/theme.h

@@ -30,6 +30,7 @@
 #include "fcitx-utils/rect.h"
 #include "fcitx/icontheme.h"
 #include "common.h"
+#include "monettheme.h"
 
 namespace fcitx::m3ui {
 enum class Gravity {
@@ -364,6 +365,10 @@ public:
     const auto &accentColorFields() const { return accentColorFields_; }
 
     void populateColor(std::optional<Color> accent);
+    // Replaces the colours of a Material style theme (one with a SurfaceColor)
+    // with colours that follow the desktop. Other themes are left as they are.
+    // Call it after load() and before populateColor().
+    void applyMonet(const MonetColors &colors);
 
     const auto &inputPanelBackground() const { return inputPanelBackground_; }
     const auto &inputPanelBorder() const { return inputPanelBorder_; }

tests/monettheme_test.cpp

@@ -0,0 +1,62 @@
+// The candidate window colours taken from a libmonet scheme must stay readable
+// for any seed, in both modes.
+//   g++ -std=c++20 -Isrc -I<libmonet>/include tests/monettheme_test.cpp
+//   (add the flags from: pkg-config --cflags --libs Fcitx5Utils)
+#include <cmath>
+#include <cstdio>
+
+#include "monettheme.h"
+
+using namespace fcitx::m3ui;
+
+static int failures = 0;
+#define CHECK_MSG(cond, ...)                                                       \
+    do {                                                                           \
+        if (!(cond)) {                                                             \
+            std::printf("FAIL line %d: %s  ", __LINE__, #cond);                    \
+            std::printf(__VA_ARGS__);                                              \
+            std::printf("\n");                                                     \
+            failures++;                                                            \
+        }                                                                          \
+    } while (0)
+
+static monet::Rgb rgb(const fcitx::Color &c) {
+    return {static_cast<std::uint8_t>(std::lround(c.redF() * 255)), static_cast<std::uint8_t>(std::lround(c.greenF() * 255)),
+            static_cast<std::uint8_t>(std::lround(c.blueF() * 255))};
+}
+
+int main() {
+    unsigned state = 4242;
+    auto next = [&] { state = state * 1664525u + 1013904223u; return static_cast<std::uint8_t>(state >> 24); };
+    std::vector<monet::Rgb> seeds = {{61, 174, 233}, {255, 176, 201}, {0, 0, 0}, {255, 255, 255}, {128, 128, 128},
+                                     {255, 0, 0},    {0, 255, 0},     {0, 0, 255}, {255, 255, 0}, {0x67, 0x50, 0xA4}};
+    for (int i = 0; i < 300; i++) seeds.push_back({next(), next(), next()});
+    for (auto seed : seeds) {
+        for (auto mode : {monet::Mode::Light, monet::Mode::Dark}) {
+            const MonetColors c = mapScheme(monet::generate(seed, mode));
+            const char *m = mode == monet::Mode::Dark ? "dark" : "light";
+            const auto surface = rgb(c.surface), fill = rgb(c.highlightFill);
+            auto pair = [&](const char *name, monet::Rgb bg, const fcitx::Color &fg, double min) {
+                CHECK_MSG(monet::contrast(bg, rgb(fg)) >= min, "%s %s, seed %s: %.2f < %.1f", m, name, monet::hex(seed).c_str(),
+                          monet::contrast(bg, rgb(fg)), min);
+            };
+            pair("candidate text", surface, c.normal, 7.0);
+            pair("candidate number", surface, c.candidateLabel, 4.5);
+            pair("candidate comment", surface, c.candidateComment, 4.5);
+            pair("typed pinyin being converted", surface, c.highlight, 4.5);
+            pair("text on the current candidate", fill, c.highlightCandidate, 7.0);
+            pair("number on the current candidate", fill, c.highlightCandidateLabel, 7.0);
+            pair("comment on the current candidate", fill, c.highlightCandidateComment, 7.0);
+            // the panel border can be seen against the panel
+            CHECK_MSG(monet::contrast(surface, rgb(c.outline)) >= 1.1, "%s border of seed %s", m, monet::hex(seed).c_str());
+            // the pill can be told apart from the panel, by tone since a container is only a few tones off the surface
+            CHECK_MSG(std::fabs(monet::toneOf(fill) - monet::toneOf(surface)) >= 3.0, "%s pill of seed %s: tones %.1f and %.1f", m,
+                      monet::hex(seed).c_str(), monet::toneOf(fill), monet::toneOf(surface));
+            CHECK_MSG(c.surface.alpha() == 245 && c.normal.alpha() == 255 && c.highlightFill.alpha() == 255, "%s alpha of seed %s", m, monet::hex(seed).c_str());
+            // dark panel in dark mode, light panel in light mode
+            CHECK_MSG((monet::toneOf(surface) < 50) == (mode == monet::Mode::Dark), "%s panel tone of seed %s", m, monet::hex(seed).c_str());
+        }
+    }
+    std::printf(failures ? "%d check(s) failed\n" : "monettheme: all checks passed\n", failures);
+    return failures ? 1 : 0;
+}